<template>
  <view>
    <my-search @click="gotoSearch"></my-search>
    <view class="scroll-view-container">
      <!-- 左滑动 -->
      <scroll-view scroll-y="true" class="left-scroll-view" :style="{height:wh+'px'}">
        <block v-for="(item,i) in cateList" :key="i">
          <view :class="['left-scroll-view-item',i===active?'active':'']" @click="activeChanged(i)">{{item.cat_name}}</view>
        </block>
      </scroll-view>
      <!-- 右滑动 -->
      <scroll-view scroll-y="true" class="right-scroll-view" :style="{height:wh+ 'px'}" :scroll-top="scrollTop">
        <view class="cate-lv2" v-for="(item2,i2) in cateLevel2" :key="i2">
          <view class="cate-lv2-title">
            /{{item2.cat_name}}/
          </view>
          <!-- 三级分类 -->
          <view class="cate-lv3-list">
                <!-- 三级分类 Item 项 -->
                <view class="cate-lv3-item" v-for="(item3, i3) in item2.children" :key="i3" @click="gotoGoodsList(item3)">
                  <!-- 图片 -->
                  <image :src="item3.cat_icon"></image>
                  <!-- 文本 -->
                  <text>{{item3.cat_name}}</text>
                </view>
              </view>
        </view>
      </scroll-view>
    </view>
  </view>
</template>

<script>
  import badgeMix from '@/mixins/tabbar-badge.js'
  export default {
    mixins: [badgeMix],
    data() {
      return {
        wh:0,
        cateList: [],
        active:0,
        // 二级分类
        cateLevel2: [],
        scrollTop:0
      }
    },
    methods: {
      async getcateList(){
        const {data:res}=await uni.$http.get('/api/public/v1/categories')
        if(res.meta.status!==200){
          return uni.$showMsg()
        }
        this.cateList=res.message
        this.cateLevel2=this.cateList[0].children
      },
      activeChanged(i){
        this.active=i
        this.cateLevel2=this.cateList[i].children
        this.scrollTop=this.scrollTop===0?1:0
      },
      gotoGoodsList(item3){
        uni.navigateTo({
          url:'/subpkg/goods_list/goods_list?cid='+item3.cat_id
        })
      },
      gotoSearch(){
        uni.navigateTo({
          url:'/subpkg/search/search'
        })
      }
    },
    onLoad() {
      // 获取当前系统的信息
      const sysInfo=uni.getSystemInfoSync()
      this.wh=sysInfo.windowHeight -50
      this.getcateList()
    }
  }
</script>

<style lang="scss">
.scroll-view-container {
  display: flex;

  .left-scroll-view {
    width: 120px;

    .left-scroll-view-item {
      line-height: 60px;
      background-color: #f7f7f7;
      text-align: center;
      font-size: 12px;

      // 激活项的样式
      &.active {
        background-color: #ffffff;
        position: relative;

        // 渲染激活项左侧的红色指示边线
        &::before {
          content: ' ';
          display: block;
          width: 3px;
          height: 30px;
          background-color: #c00000;
          position: absolute;
          left: 0;
          top: 50%;
          transform: translateY(-50%);
        }
      }
    }
  }
}
.cate-lv2-title {
  font-size: 12px;
  font-weight: bold;
  text-align: center;
  padding: 15px 0;
  }
  .cate-lv3-list {
    display: flex;
    flex-wrap: wrap;
  
    .cate-lv3-item {
      width: 33.33%;
      margin-bottom: 10px;
      display: flex;
      flex-direction: column;
      align-items: center;
  
      image {
        width: 60px;
        height: 60px;
      }
  
      text {
        font-size: 12px;
      }
    }
  }
</style>
